Ever since I killed a certain character, people have been talking after dying. Context:

So... I walked into the Emperor's room aboard the Katariah, expecting a full-on fight with the guards, some agents, and the man himself. Instead I found the Emperor telling me calmly to kill him. He was, in my opinion, quite rude about it indeed – kept going on about how he didn't have all day and whatnot, didn't notice that I was busy looting his chests. In any case, I wanted it to look better than "walk up to him and stab him in the face," so I drank my invisibility potion, walked up behind him, and backstabbed him. I got my epic animation, but... to my surprise, as I was about to leave the room, I see in the subtitles, "Go on, I'm not going to fight you." This remained even as I jumped up and down on his dead body, dragged it across the floor, lit it on fire, etc.

The body only stopped talking when I left the room, so it wasn't exactly a persistent problem, but I have had the same issue ever since; people I brutally murder like to talk back to me after they're dead. If anyone else has had this issue, how can I fix it?

Xbox 360, so no commands. This quest is aboard the Katariah, which only exists when one gets pretty far through a certain assassin-y questline. In addition, the NPC killed had no actual conversation options, just one quote.
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Istvan ChungFeb 14 '12 at 4:00